/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.catalina.ha;

import org.apache.catalina.LifecycleException;
import org.apache.catalina.tribes.ChannelListener;

import java.io.File;
import java.io.IOException;

/**
 * A <b>ClusterDeployer</b> interface allows to plug in and out the
 * different deployment implementations
 *
 * @author Filip Hanik
 */
public interface ClusterDeployer extends ChannelListener {
	/**
	 * Descriptive information about this component implementation.
	 */
	public String info = "ClusterDeployer/1.0";

	/**
	 * Start the cluster deployer, the owning container will invoke this
	 *
	 * @throws Exception - if failure to start cluster
	 */
	public void start() throws Exception;

	/**
	 * Stops the cluster deployer, the owning container will invoke this
	 *
	 * @throws LifecycleException
	 */
	public void stop() throws LifecycleException;

	/**
	 * Install a new web application, whose web application archive is at the
	 * specified URL, into this container and all the other
	 * members of the cluster with the specified context name.
	 * <p>
	 * If this application is successfully installed locally,
	 * a ContainerEvent of type
	 * <code>INSTALL_EVENT</code> will be sent to all registered listeners,
	 * with the newly created <code>Context</code> as an argument.
	 *
	 * @param contextName The context name to which this application should
	 *                    be installed (must be unique)
	 * @param webapp      A WAR file or unpacked directory structure containing
	 *                    the web application to be installed
	 * @throws IllegalArgumentException if the specified context name
	 *                                  is malformed
	 * @throws IllegalStateException    if the specified context name
	 *                                  is already attached to an existing web application
	 * @throws IOException              if an input/output error was encountered
	 *                                  during installation
	 */
	public void install(String contextName, File webapp) throws IOException;

	/**
	 * Remove an existing web application, attached to the specified context
	 * name.  If this application is successfully removed, a
	 * ContainerEvent of type <code>REMOVE_EVENT</code> will be sent to all
	 * registered listeners, with the removed <code>Context</code> as
	 * an argument. Deletes the web application war file and/or directory
	 * if they exist in the Host's appBase.
	 *
	 * @param contextName The context name of the application to be removed
	 * @param undeploy    boolean flag to remove web application from server
	 * @throws IllegalArgumentException if the specified context name
	 *                                  is malformed
	 * @throws IllegalArgumentException if the specified context name does
	 *                                  not identify a currently installed web application
	 * @throws IOException              if an input/output error occurs during
	 *                                  removal
	 */
	public void remove(String contextName, boolean undeploy) throws IOException;

	/**
	 * call from container Background Process
	 */
	public void backgroundProcess();

	/**
	 * Returns the cluster the cluster deployer is associated with
	 *
	 * @return CatalinaCluster
	 */
	public CatalinaCluster getCluster();

	/**
	 * Associates the cluster deployer with a cluster
	 *
	 * @param cluster CatalinaCluster
	 */
	public void setCluster(CatalinaCluster cluster);

}
